//----------------------------------------------------------------------------
void WrigglingSnake::ModifyCurve ()
{
// Perturb the snake medial curve.
float time = (float)GetTimeInSeconds();
for (int i = 0; i < mNumCtrlPoints; ++i)
{
Vector3f ctrl = mCenter->GetControlPoint(i);
ctrl.Z() = mAmplitudes[i]*Mathf::Sin(3.0f*time + mPhases[i]);
mCenter->SetControlPoint(i, ctrl);
}
UpdateSnake();
}
//----------------------------------------------------------------------------
void WrigglingSnake::ModifyCurve ()
{
// perturb the snake medial curve
float fTime = GetTimeInSeconds();
for (int i = 0; i < m_iNumCtrl; i++)
{
Vector3f kCtrl = m_pkCenter->GetControlPoint(i);
kCtrl.Z() = m_afAmplitude[i]*Mathf::Sin(3.0f*fTime+m_afPhase[i]);
m_pkCenter->SetControlPoint(i,kCtrl);
}
UpdateSnake();
}
//----------------------------------------------------------------------------
void WrigglingSnake::CreateSnakeHead ()
{
VertexFormat* vformat = VertexFormat::Create(2,
VertexFormat::AU_POSITION, VertexFormat::AT_FLOAT3, 0,
VertexFormat::AU_COLOR, VertexFormat::AT_FLOAT3, 0);
int vstride = vformat->GetStride();
// Create the snake head as a paraboloid that is attached to the last
// ring of vertices on the snake body. These vertices are generated
// for t = 1.
int numSliceSamples = mSnakeBody->GetNumSliceSamples();
mSlice = new1<Vector3f>(numSliceSamples + 1);
// Number of rays (determined by slice samples of tube surface).
int numRays = numSliceSamples - 1;
// Number of shells less one (your choice, specified in application
// constructor).
int numShellsM1 = mNumShells - 1;
// Generate vertices (positions to be filled in by UpdateSnakeHead).
int numVertices = 1 + numRays*numShellsM1;
VertexBuffer* vbuffer = new0 VertexBuffer(numVertices, vstride);
VertexBufferAccessor vba(vformat, vbuffer);
Float3 darkGreen(0.0f, 0.25f, 0.0f);
for (int i = 0; i < numVertices; ++i)
{
vba.Color<Float3>(0, i) = darkGreen;
}
// Generate triangles.
int numTriangles = numRays*(2*numShellsM1 - 1);
int numIndices = 3*numTriangles;
IndexBuffer* ibuffer = new0 IndexBuffer(numIndices, sizeof(int));
int* indices = (int*)ibuffer->GetData();
for (int r0 = numRays - 1, r1 = 0, t = 0; r1 < numRays; r0 = r1++)
{
*indices++ = 0;
*indices++ = 1 + numShellsM1*r0;
*indices++ = 1 + numShellsM1*r1;
++t;
for (int s = 1; s < numShellsM1; ++s)
{
int i00 = s + numShellsM1*r0;
int i01 = s + numShellsM1*r1;
int i10 = i00 + 1;
int i11 = i01 + 1;
*indices++ = i00;
*indices++ = i10;
*indices++ = i11;
*indices++ = i00;
*indices++ = i11;
*indices++ = i01;
t += 2;
}
}
mSnakeHead = new0 TriMesh(vformat, vbuffer, ibuffer);
mSnakeHead->SetEffectInstance(VertexColor3Effect::CreateUniqueInstance());
mSnakeRoot->AttachChild(mSnakeHead);
UpdateSnake();
}
